Figure 6: Accelerated corneal collagen crosslinking Group 3 (epithelium-off): Riboflavin 0.1% (dextran free) plus HPMC, 10 minutes of corneal soaking, UV-A power at 30 mW/cm2 (Energy dose: 7.2 J/cm2), 4 min exposure time. Postoperative confocal scans revealed lacunar edema (upper left light blue arrow-a) with keratocytes apoptosis (upper right light blue arrow-b) and increased density of extracellular matrix (bottom left light blue arrow-c). A transition between the hypo-cellular stroma and stromal tissue unreached by the treatment (vertical transition area) is showed in the bottom left - d scan, with an estimated penetration of 155 μm (range 140-180 μm).